The invention relates to a weighting arm for drafting systems of spinning and roving frames with built-in cleaning device according to the description of claim 1.
In the different drafting systems applied today in the textile industry there are still mostly either stationary cleaning plates covering all lines of top rollers or individual cleaning rolls for the different top rollers in action. The well known disadvantage of both arrangements is the permanent accumulation of dust and fibers on the felts of plates and cleaner rolls. If not cleaned in short intervals the accumulated material detaches by itself in dust accumulations which are carried on from the stock in the roving path leading then to unevenness of the roving path and yarn or to stoppage of the frame. Especially on roving frames such stops can reduce the efficiency of the machine drastically.
New machines in Europe are currently preferably equipped with a rotating cleaning device known from German patent description DE-AS No. 1092351, in which a cleaning tape is pressed by an iron roll on the back top roller for its permanent drag. In spite of the relatively heavy iron roll the drag is interrupted when uneven deposits of dust and fibers on th cleaning tapes or around the axles of the iron roller arise. In addition to the inconveniences of uneven roving, the machine is sometimes stopped.
New machines built in the Far East have mostly a positive drive for the rotating cleaning arrangement. Such a device is described in German patent specification DE-OS No. 2422050. The disadvantages here are the relatively high installation costs and the enclosed space around the drafting units reducing facility of inspection and accessibility for the worker.